Problem: What is the distance, in units, between the points $(-3, -4)$ and $(4, -5)$? Express your answer in simplest radical form.
Solution: We use the distance formula:  \begin{align*}
\sqrt{(4 - (-3))^2 + ((-5) - (-4))^2} &= \sqrt{7^2 + (-1)^2} \\
&= \sqrt{49 + 1} \\
&= \sqrt{50} \\
&= \boxed{5\sqrt{2}}.
\end{align*}